Question

How to fix the P1401 problem on my 2000 Ford F150 5.4L?

Answer 1

P1401 DPFE sensor circuit high

This is for the EGR system, when it is circuit high check for its connection, Circuit high conditions occurs when there is a disconnection of that sensor either external of the sensor or internal

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The DPFE is for the EGR system. P1401 is a malfunction of the DPFE sensor

Answer 2

P1401 FORD Code - DPFE Sensor Circuit High
Read more: https://www.autocodes.com/p1401_ford.html